It's the loudest show I've been to since Killing Joke in 1981. Which is odd, because the band on stage, and the singer no one can take their eyes off, are the polar opposite of a goth-metal noise group. The (white) guitarist and (black) keyboard player are sporting the most spectacular Afros this side of a Seventies Pam Grier movie. And the singer is so charismatic, in such an old-fashioned, painfully beautiful, post-Hendrix superfreak way, that he's transforming the pub venue surroundings of the Water Rats in London's King's Cross into a compelling mix of Sly Stone at Woodstock and Terence Trent D'Arby on The Tube circa 1987.

The singer strikes a pose, and the lights illuminate the kind of pop star face you couldn't improve with all the CGI and Photoshop in the world. Short, immaculately messy 'fro. Dark mixed-race skin. Chinese eyes. Razor-sharp cheekbones. Lusciously kissy lips.

The boy is David Jordan, 22-year-old singer-songwriter prodigy and the Mercury label's Big New Pop Hope. They're surely gambling on a winner, because this is the kind of universal pop and dreamboat charisma that could well be stealing the show at The Brits 2008. He is playing the Water Rats as the final show in a brief residency, and there is a feeling, among the impressed crowd, that there's unlikely to be an opportunity to see this ball of energy in a small venue again.The set ends, our pummelled ears buzz, and, as the pocket-sized powerhouse tells us he loves us and wiggles his way offstage in his leopard-print leggings, the final weapon in his world domination arsenal is revealed. David Jordan has the world's tiniest arse.

'I choose my stage outfits in my dreams. Really! I dream about what I'm wearing, then I wake up ... all of my clothes are just lying in a heap on my bedroom floor, so I just rifle through until I find what I wore in the dream. And that's my outfit that night.'

David Jordan is a dreamy kind of boy. It's around three hours before the Water Rats show, in a photographic studio in Hoxton, and for someone who looks like he does, has been writing accomplished soulful pop-rock sings since he was 11, and whom his producer, the ABC/Frankie Goes to Hollywood/Seal/Buggles master of widescreen hi-tech pop Trevor Horn, reckons 'can sing the paint off the walls', Jordan seems refreshingly free of ego. Not that he's exactly a typical north London geezer. His first musical hero was Prince, and he's fully embraced aspects of the Minneapolis Maestro's camp, androgynous and somewhat other-worldly persona. But, as we talk in the studio's empty canteen, he is sweetness itself. Perhaps it's down to the best piece of advice he reckons he ever received from his mentor, whose forced absence casts a shadow over the promotion of his forthcoming first album, Set the Mood. The piece of advice was: always be polite. And Jordan's certainly taken it to heart, even though he wears shades all the way through our interview, just like an old-school rock star. His mentor isn't around to mind his manners, though. She's been in a coma for over a year.

Jill Sinclair has been a major player in the music business for 20 years, not least as Trevor Horn's wife, manager and business partner. In June of last year, Horn and Sinclair's 22-year-old son Aaron accidentally shot his mother in the neck with his air rifle, severing an artery. Jill has been in a coma ever since. Unsurprisingly, work on Jordan's album ground to a halt as Trevor Horn's family and friends tried to come to terms with such a random tragedy.

'It had a big impact on everything,' says Jordan. 'Everyone was very shocked. God knows, I was shocked. I was ... devastated. But ... you know ...' A long pause. A long look out of the window. He seems to be alighting on some private memory of Jill Sinclair. It must be a nice one, because he laughs.

'It's funny. I don't remember much about things, usually. But when someone's taken from you so quickly, you suddenly remember every conversation you ever had. It all comes back to me. I hear her voice in my ear saying, "Don't do this and make sure you do that!" And it's nice, because it makes me feel like she's still there.'

For a debut artist of such tender years, Jordan has quite a story. Born to a mother from Montserrat and a father from Calcutta, he admits to some teenage insecurity about his racial make-up. 'I just wanted to blend in,' he says.

Jordan's parents split when he was 10. 'I remember 'cause the head teacher of my school tapped me on my shoulder and was like, "Divorce can be a really hard thing" and I was just like, "What's he talking about?" It hadn't affected me as much as it can affect kids. I still got to see them both.'

Nevertheless, he chose to live with his grandmother until he blagged a council flat in Finchley aged 16, and embarked upon what he calls 'my wild years'. Obsessed with songwriting and a record deal, he would study drama at college during the day, work at Starbucks in New Oxford Street in the evening, and then head to Fortress Studios in Old Street to work on songs with his producer friend Jack Freegard. This punishing schedule wasn't just fuelled by youthful enthusiasm. 'Whatever we could get our hands on at that time we would pile into our bodies to keep us awake,' says Jordan. 'When you're that young and you're experimenting with things ... it was a great period.'

You don't look like you've ever taken a drug in your life.

'Ha! Well, you know, that's good because I don't any more. Because it was so short-lived ... it was like a moment, two years maximum. Had I been there for longer I would have fallen into a deep hole.'

The hole he did fall into was one based entirely around his teenage desperation for success. He was running with a crowd of young pop wannabes, all of whom got signed to Simon Fuller's management company, 19. All except David, that is. One of them was a pre-infamy Amy Winehouse. 'We met when I was younger. I was 14. We had mutual friends, and I was invited round and she was downstairs playing her guitar. My first visual image of her was the black hair, white skin, red lips ... and she had a red dress on as well. She was in the kitchen and I remember walking downstairs, 14 years old, and I was drinking absinthe. Ha! We said hi and that was it. Years later we'd hang out, 'cause she had a place in East Finchley with a friend. We'd sit and play Sega Megadrive.'

Jordan appears to carry some bitterness about what happened next. Amy went on to be a star. Their mutual friends John the White Rapper and Tyla James also got signed, albeit with no success. But no one was interested in David, and he felt abandoned by his friends. 'They were all going out doing their things and I was never invited. It's like kids in the playground, when your friends run off saying, "I don't wanna be your friend any more!" I'd worked a lot harder than they had, and it seemed to be just falling into their laps. I was just going, "Why? Why?" Looking back it was a really, really upsetting time for me.'

I ask about his take on Amy's recent descent into tabloid drug fiend status. 'The industry, naturally, has tainted her. She was very ... let's just say different to how she is now. She seemed happier.'

This cynical attitude toward the music biz comes to mind when I ask Trevor Horn whether the boy he first met was in need of a confidence boost. 'He never said he'd lost confidence to me,' Horn ponders. 'But I know most people do before they have any kind of success, and that's why sometimes some have a chip on their shoulder once they get successful - they want to get their own back on a whole bunch of people. But that's a complete waste of time. And I don't think David's like that at all.'

Set the Mood should ensure that Jordan puts his teenage disappointments a long way behind him. The first single, 'Place in My Heart', is an irresistible slice of modernised Michael Jackson, while 'Sun Goes Down' is, as Horn describes it, 'hip hop-meets-klezmer'. And if the rest of the album isn't quite an Off the Wall or a Purple Rain, it is big, ambitious and uplifting enough - in a very Seal-like way, it must be said - to make fans of Proper Pop want to see who's making this nouveau-retro noise. And once they see him, his charisma and vocal virtuosity should do the rest.

The boy wonder is also disarmingly honest. Towards the end of the interview, I ask him about the album's closing track, 'On the Money'. 'I don't really like it,' he says. 'I sound like a bit of a drip.' But it does include a striking line, David. It goes: 'I've learned from teachers that could orchestrate the whole wide world'. Who is that about?

'Jill Sinclair and Trevor Horn. Every time I sing it I remember how Jill used to be. She was so confident, so sure. I want to be like her when I'm older. '

Broken home. Rejection and betrayal. Sudden tragedy. But Set the Mood is no tear-stained confessional and Jordan wears his angst lightly. Is it all going to come later, in a welter of gloomy songs and angry interviews?

'Everyone has situations in their family life that are obstacles to overcome. I haven't had an easy ride. But I haven't had a difficult one.'

He smiles, coyly. 'I might have some stories. But not just yet.'

· The single, 'Place in My Heart', is released on 22 October, and the album, 'Set the Mood', is out on 29 October, both on Mercury